ISO 19905-1:2023

This document specifies requirements and provides recommendation and guidance for the elevated site-specific assessment (SSA-E) of independent leg jack‑up units for use in the petroleum and natural gas industries. It addresses:

a)       occupied non-evacuated, occupied evacuated and unoccupied jack‑ups;

b)       the installed (or elevated) phase at a specific site.

It also addresses the requirement that the as-installed condition matches the assumptions used in the assessment.

This document does not address the site-specific assessment of installation and removal (SSA-I).

To ensure acceptable reliability, the provisions of this document form an integrated approach, which is used in its entirety for the site-specific assessment of a jack‑up.

When assessing a jack-up operating in regions subject to sea ice and icebergs, it is intended that the assessor supplements the provisions of this document with the relevant provisions relating to ice actions contained in ISO 19906 and procedures for ice management contained in ISO 35104. This document does not address design, transit to and from site, or installation and removal from site.

This document is applicable only to independent leg mobile jack-up units that are structurally sound and adequately maintained, which is normally demonstrated through holding a valid recognized classification society, classification certificate. Jack‑ups that do not hold a valid recognized classification society certificate are assessed according to the provisions of ISO 19902, supplemented by methodologies from this document, where applicable.

NOTE 1        Well conductors can be a safety-critical element for jack‑up operations. However, the integrity of well conductors is not part of the site-specific assessment process for jack‑ups and is, therefore, not addressed in this document. See A.1 for guidance on this topic.

NOTE 2        RCS rules and the IMO MODU code (International Maritime Organisation Mobile Offshore Drilling Unit code) provide guidance for the design of jack-ups.